Molecular and Translational Studies in Hematologic Disorders

申请NHLBI R35杰出研究员奖是为了探索血浆蛋白的作用 血管性血友病因子(VWF)在2型血管性血友病(VWD)和镰状细胞病(SCD)中的表达 我们的目标是将涵盖这些领域的2笔R01赠款合并为一笔更有凝聚力、更灵活的赠款 追踪有趣的科学线索。在这两种疾病中，VWF的参与方向相反， 在2型VWD中功能失调，以小多聚体为主，并且丰富，功能亢进， 镰状细胞病很多。对于vwd，我们将探索广泛表型变异的分子基础。 与单个突变相关，检验这种变异性的重要决定因素包括 突变单体掺入多聚体VWF的百分率和MET对VWF蛋白的降解程度。 同种异构酶ADAMTS13。我们还将探讨2型VWD患者的血小板收缩功能是如何受到影响的，包括 分别测定血浆和血小板VWF的贡献。最后，我们将研究耐人寻味的 在2A型和2B型VWD中，对止血缺陷有显著贡献的可能性是 过度的VWF蛋白降解产生的VWF片段。在SCD，我们有证据表明监管存在缺陷 最大的VWF多聚体，没有被ADAMTS13充分切割。我们将调查……的基础 并测试旨在减弱VWF活性的各种措施是否会改善 SCD动物模型的病程。最后，我们将探索一种引人入胜的 我们在研究N-乙酰半胱氨酸对SCD影响的过程中观察到：药物诱导 病人血液中非常稠密的红细胞迅速流失。我们假设这种影响是由 减少氧化的鬼影蛋白残留量，并将探索其可能得到更多治疗的可能性 有效地通过氨基酸L-麦角硫蛋白，它存在于蘑菇和其他食物中，是浓缩的- 由一种高度特异的转运蛋白在红细胞中运输。总而言之，这些研究使用最先进的工具来研究 在两种重要的人类疾病中存在令人困惑的问题，并期待着改善治疗方法 受影响的病人。R35资金机制提供了灵活性，以跟踪发现的有趣线索- 在这些研究过程中发生的错误，增加了患者受益的可能性。

This application for an NHLBI R35 Outstanding Investigator Award is to explore the role of the plasma protein von Willebrand factor (VWF) in 2 diseases, type 2 von Willebrand disease (VWD) and sickle cell disease (SCD), and our goal is to roll 2 R01 grants covering these areas into a single, more cohesive grant with more flexibility to follow interesting scientific leads. In these two diseases, the involvement of VWF is in opposite directions, dysfunctional and with predominantly small multimers in type 2 VWD, and abundant, hyperfunctional, and large in sickle cell disease. For VWD, we will explore the molecular basis of the broad phenotypic variability associated with single mutations, testing the hypothesis that important determinants of this variability include percentage of mutant monomer incorporation into multimeric VWF and extent of VWF proteolysis by the met- alloprotease ADAMTS13. We will also explore how platelet contractility is affected in type 2 VWD, including to determine the respective contributions of plasma and platelet VWF. Finally, we will examine the intriguing possibility that in types 2A and 2B VWD a significant contribution to the hemostatic defect is provided by VWF fragments produced by excessive VWF proteolysis. In SCD, we have evidence of defective regulation of the largest VWF multimers, which are inadequately cleaved by ADAMTS13. We will investigate the basis of this lesion, and test whether a variety of measures aimed at attenuating the activity of VWF will improve the course of the disease in an animal model of SCD. Finally, we will explore the molecular basis of a fascinating observation we made in the course of studying the effect of N-acetylcysteine in SCD: that the drug induced rapid loss of very dense erythrocytes from the blood of patients. We hypothesize that the effect is caused by reduction of oxidized spectrin residues and will also explore the possibility that it may be treated even more effectively by the amino acid L-ergothioneine, which is present in mushrooms and other foods and is concen- trated in erythrocytes by a highly specific transporter. Together, these studies use state-of-the-art tools to ex- plore perplexing problems in two important human diseases, with the expectation of improved therapies for the affected patients. The R35 funding mechanism provides the flexibility to follow interesting leads discov- ered during the course of these studies, increasing the likelihood that patients will benefit.